Rock the Bells: The 'Bastard' is back onstage

One day after Eazy-E seemingly rose from the grave to take the stage with his old cohorts in Bone Thugs-n-Harmony, Ol' Dirty Bastard accomplished a similar trick at Shoreline Amphitheatre.

The reappearance of ODB -- the legendary rapper who's been dead since 2004 -- was one of the true highlights of the 2013 Rock the Bells festival, which took over the Mountain View venue on Saturday and Sunday.

ODB and Easy-E both appeared via the virtual performance technology known as Pepper's ghost, the same method used to famously resurrect Tupac Shakur at the Coachella festival last year. The process uses a reflective screen and lighting techniques to produce a result that is like a hologram, although, technically speaking, it's not one.

The effect worked quite well on Sunday. From my vantage point, at the back of the lower reserved section of the Shoreline bowl, it really looked like ODB was up there rapping with his old partners in Wu-Tang Clan. It was even more believable than what was witnessed on Saturday with virtual Eazy-E and real-life Bone Thugs.

It was a moving moment, albeit one that was also quite bizarre. After all, ODB's final public performance with Wu-Tang was at the first-ever Rock the Bells, which was held in Southern California in 2004. So, it's only fitting that the "reunion" would happen during the 10th anniversary of the festival.

The ODB moment of Wu-Tang's headlining set only lasted a few minutes, but it will likely remain in fans' memories for years to come.